New Study: Scientists Find Recent Uk Flooding Is Not Unprecedented

From the GWPF Observatory

This new paper presents the first coherent large-scale national analysis undertaken on historical flood chronologies in Britain, providing an unparalleled network of sites (Fig. 1), permitting analysis of the spatial and temporal distribution of high-magnitude flood patterns and the potential mechanisms driving periods of increased flooding at a national scale (Britain) since AD 1750.


The apparent increase in flooding witnessed over the last decade appears in consideration to the long-term flood record not to be unprecedented; whilst the period since 2000 has been considered as flood-rich, the period 1970–2000 is “flood poor”, which may partly explain why recent floods are often perceived as extreme events. The much publicised (popular media) apparent change in flood frequency since 2000 may reflect natural variability, as there appears to be no shift in long-term flood frequency.


Abstract

The last decade has witnessed severe flooding across much of the globe, but have these floods really been exceptional? Globally, relatively few instrumental river flow series extend beyond 50 years, with short records presenting significant challenges in determining flood risk from high-magnitude floods. A perceived increase in extreme floods in recent years has decreased public confidence in conventional flood risk estimates; the results affect society (insurance costs), individuals (personal vulnerability) and companies (e.g. water resource managers). Here, we show how historical records from Britain have improved understanding of high-magnitude floods, by examining past spatial and temporal variability. The findings identify that whilst recent floods are notable, several comparable periods of increased flooding are identifiable historically, with periods of greater frequency (flood-rich periods). Statistically significant relationships between the British flood index, the Atlantic Meridional Oscillation and the North Atlantic Oscillation Index are identified. The use of historical records identifies that the largest floods often transcend single catchments affecting regions and that the current flood-rich period is not unprecedented. […]

click on image to enlarge

Summary

The apparent increase in flooding witnessed over the last decade appears in consideration to the long-term flood record not to be unprecedented; whilst the period since 2000 has been considered as flood-rich, the period 1970–2000 is “flood poor”, which may partly explain why recent floods are often perceived as extreme events. The much publicised (popular media) apparent change in flood frequency since 2000 may reflect natural variability, as there appears to be no shift in long-term flood frequency (Fig. 5). In reviewing the flood series for European systems for which long flood series have been reconstructed, a complex picture is identified; whilst flood-rich phases appear synchronous across many systems (1765–1780) others show less synchronicity (1920s), whereas a number of prominent floodrich phases at a European scale appear subdued or are not evident in the British FI (1750s).

The principal findings of this work are that of the strong correlations between flood-rich/flood-poor phases and solar magnetic activity, AMO and NAOI, indicating a clear driver for flooding patterns across Britain. The specific mechanisms that govern the relationship between the spatial/temporal distribution of flood clusters and solar activity remain unclear. This work suggests that high-magnitude flood-rich periods relate to negative NAOI across much of the country, in western catchments with a stronger westerly airflow signal significantly correlating to positive NAOI, with reasonable correspondence with previously diagnosed periods of climatic variability identified from individual series from across Europe. It also identifies the importance of the Atlantic Multidecadal Oscillation as a clear correlation is shown between higher North Atlantic sea temperatures and increased severe flood events across much of Britain. It is worth noting that when the threshold is reduced to the 0.8 percentile of events (Fig. 5), significant correlations remain between the British FI and summer, winter, annual AMO (1850) and NAOI (Trouet et al., 2009). The inclusion of historical flood information provides a better understanding of long-term flood patterns. The detection of flood-rich periods and attribution to periods of climatic change are tentative. The historical records still hold a wealth of untapped information for which specific discharges cannot be estimated, but from which indices could be extracted in the future (Barriendos and Coeur, 2004). The wealth of information presented by the historical records presents valuable new information for flood risk assessment and management (Kjeldsen et al., 2014); as new flood chronologies become available, more detailed and complete indices-based chronologies will improve the resolution and enhance understanding of flood-rich and flood-poor periods, presenting a more complete depiction of the role of climate and extreme floods. Extending the records back to a millennial time frame is possible, providing valuable insights into long-term trends and patterns of flood frequency and potential climatic drivers of flooding.


Neil Macdonald and Heather Sangster (2017), Hydrology and Earth System Sciences 21: 1631-1650.
Full paper

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90 thoughts on “New Study: Scientists Find Recent Uk Flooding Is Not Unprecedented

  1. Looks like a decent, well referenced paper from an expert with a track record of publictions in the field. The use of historical data to infer a consistent flood index is surely very useful, and necessary if we are to try to compare current conditions with historical ones.

  2. Since I was was born the worlds population has doubled and the UK population has increased by about 30%. The perception of increased flooding must be put into context with: [1] the increase in the amount of people living in areas that flood; [2] the decrease in areas that are allowed to flood and where excess water goes; [3] the affect of any development on water runnoff as most urban areas will and are expected to be well drained, although this includes farmland; [4] the fact that the UK has a reputation for rain especially over public holidays.

    • Stephen

      I also know from experience that people are far more likely to complain about flooding than in the past, whereby with fewer pocessions and a more rural way of life and more help from neighbours the acceptance of natural occurrences was fairly widespread
      tonyb

      • Or complain about anything for that matter, it just seems to be our natural state anymore. The less we actually have to complain about the more complaining we do.

      • Add to the ceaseless complaining without end,,,,the Continuous News Cycle. Complete with a never ending endless supply of happysmilycheery “news anchors”, many of who are ecstatically happysmilycheery to stand in the middle of hurricanes, tornadoes, and blizzards in order to assure the masses that everything is simply craptacular and it is all their viewers’ fault. And send money.

      • “climatereason June 19, 2017 at 10:05 am
        Stephen

        I also know from experience that people are far more likely to complain about flooding than in the past, whereby with fewer pocessions and a more rural way of life and more help from neighbours the acceptance of natural occurrences was fairly widespread
        tonyb”

        Succinct and well stated tonyb!

      • AND, increased insurance costs have far more to do with “new for old” changes in insurance policies than any increase in dramatic weather patterns today. Yet another example of the “authorities” manipulating the data for political ends!

      • Tony, flooding in the Severn valley increased in the early 1960s following widespread planting of coniferous forests throughout the welsh hills (the runoff was much quicker than from the native woodlands). Flood control reservoirs such as Clwedog were built to alleviate this. There isn’t a constant background to this. Near Worcester cathedral there are plaques on a wall marking notable flood levels back to 1672, the highest are 1770, followed by 1947, 1886 and 2007, 2014 and 2000 are up there too not exactly sure their actual position.
        http://www.worcesternews.co.uk/resources/images/3423035/?type=responsive-gallery-fullscreen

    • I fully agree with you. I’ve brought up these points myself in comment sections. Articles that state that increased storm damages are do to climate change causing more destruction… It’s not because the storms are stronger or more frequent – which they are not – it’s because of population growth and more buildings to become damaged, that didn’t exist during past storms and are built in places where storms happened more frequently, such as the central USA where tornado’s occur. Decades in the past those areas had fewer residents and they built on the higher grounds because the lower lands often flooded, now people have increased and are building on those lower lands, that when flooding occurs causes more structural damages. The same happened to all the coastal properties and valley’s between or near mountains. I’ve often said people are stupid for all our intelligence, when you ignore the high water and storm damage land markers and build within them.

      • This reminds me of a case we had quite a few years ago now. A man bought property on the river and wanted to build a house right in the 5 year flood plain, his building permit was denied. He sued the county and won in court the right to build his house, the whole proceedings had been played out in the news as the battle had caught public interest due to the stupidity. House wasn’t even completed when the news crew showed it being wiped out by a flood…

    • … complain about anything…
      This is the driver behind the increasing use of the phrase: ‘Suck it up, Buttercup’

    • “The perception of increased flooding must be put into context with:”

      5. Decreased dredging of rivers per Green mandates from the EU and UK government collaboration with them.

      • 6. Flood controls. A few years ago the US Corp of engineers began reversing the flood and drainage work they had done in Florida around 100 years ago. This drainage and flood control not only drained areas like Lake Okeechobee but increased flood damage downstream because the volume of rivers had been reduced by straightened; the river gradient had been increased by straightening; the volume and pace of freshwater flushing into tidal areas increased. The work of undoing this was to put meandering rivers back into their natural channels.

    • The EU Directive on water, whereby river dredging was stopped and the policy oif letting rivers “reclaim their floodplanes” has a lot to do with it too. Check the GWPF site for the relevant newspaper articles

      • Coupled with the “Habitats Directive”! Typical of the mentality, anything negative that could attributed to their “policies” must be officially attributed to Climate Change along with habitat destruction!

  3. This is just good research, finding gaps in current knowledge, and doing the basic work to fill those gaps. If the EPA and NOAA had been working along the same lines they might not have wasted numerous billions of taxpayer money of the last decade, and we might have some useful information.

  4. A frequent line in media reports is ‘these floods are unprecedented, there haven’t been floods this bad since 1701’

    • Meanwhile, in the US: ‘these floods are unprecedented, there haven’t been floods this bad since 2001’

      • Missing completely the obvious common sense point, that clearly it must have happened before to be able to make such ridiculous comparisons!!

  5. I am just reading Bill Bryson’s book on 1927, and was surprised at the extent of the Mississippi floods which had three times the volume of water flowing than the 1993 floods. There were also a number of freak weather events. So what’s new?
    We have has a number of extreme rainfalls in Somerset that have led to flooding, notably 1917, 1924 and 1968, when up to 9 inches of rain fell in one day.

    • The 1927 and 1973 floods each put over 125 cubic nautical miles of water in the Gulf of Mexico.
      Gunter, G. 1979. The annual flows of the Mississippi River. Gulf Research Reports. 6(3):283-290. I studied the 1973 event some. It almost went into the Atchafalaya. Awesome!

      • H.D.,
        Those not familiar with the lower Mississippi River system will not understand ” the Atchafalaya.”
        So: The name is that of a large low elevation basin west of the Mississippi River. The U. S. Army designed structures [about here: 31.088336, -91.605488 ] permit high flow of the River to be diverted, and reduce flooding in New Orleans and other areas.

      • Good point, the Atchafalaya River (through the basin) could have taken the dominant flow, already lots of flow was diverted there. Large erosion hole migrated toward the structure holding the MIssissippi. Geologists have long thought it would eventually go there, but it held. Impressive views of area on Google Earth.

      • And don’t forget the Pearl River Flood Control Program. Lots of acreage that was routinely flooded was converted into farm land. Look all along the Gulf Coast and you find areas that were flood plains that were levied in to “reclaim” land for human use. Good/bad, it has multiple side effects, more widespread flooding at times is one of them.

  6. As far as I can tell, Britain is flood poor. link Also, as far as I can tell, the fatal floods in Britain appear to be near the shore and associated with storm surges or possible tsunamis.

      • One of the ladies I know is from Lahore Pakistan. The other day she was waxing poetic about the wonderful monsoons they get there.

        I always thought monsoons brought a lot of rain. If this link is to be believed, Lahore gets about two and a half inches of rain in July during the monsoon season. If that’s all it takes, it sounds like London, England, is in a permanent monsoon season. link

        I have a nasty feeling that I’m missing something here.

    • Lahore sub-tropical hot steppe climate annual rainfall around 24 inches
      London temperate oceanic climate annual rainfall around 24 inches

      Just spread a bit more evenly in Londoninium

  7. There have been some catastrophic floods round here in the last few years, with whole streets of people made homeless. However, the interesting thing is that rainstorms that caused these floods didn’t seem to be exceptional.

    Years ago when I was a student there was one lulu of a storm in Edinburgh, with the road outside turned into a river and water running down the light fitting on the first floor of a four-storey building with a somewhat dodgy roof. Nobody got flooded out, though, and it was gone in minutes after the rain stopped. I don’t recall seeing rain of that intensity recently.

    The recent problems seem to be due to a failure to maintain watercourses clear of weeds and obstructions, combined with hill farming policies which have stripped the vegetation which once slowed the runoff from the hills.

    • “The recent problems seem to be due to a failure to maintain watercourses clear of weeds and obstructions”, indeed, thanks to the Eco-fundamentalists who now control the regulations in this area, mostly emanating from the EU.

  8. Unfortunately the MSM shapes and controls the narrative on …… well … just about everything. It would have been easy and provided some journalistic integrity to research recent flooding in the UK and report the truth that there is nothing ‘unprecedented’ about the recent flooding. People would have been glad to receive that news. Claims that catastrophe sells more newspapers is baloney since newspapers are the secondary source of information to TV & internet these days. It’s obviously the case where the narrative IS the story.

    • Not just the MSM, the science research centres push the publicity and funding-friendly narrative at every opportunity, to the point where a reputable MSM would cry foul.

      • Yes, the next few days in southwestern U.S. it is supposed to be hot (110°F – 120°F) which has happened before, but the MSM is saying that we can expect it more often because of global warming. During the winter if there is extraordinary cold or snow, they say it is due to climate change. Since such momentary departures from the norm will always be with us, I fear that the religion of catastrophic man-made climate change will also always be with us.

      • Yep, temps above 100 in June in New Mexico, Arizona and Texas has to be ‘unprecedented”! It fits the agenda so well there just ain’t no way it could be normal. No way, dude!

    • “Quite what will the UK’s snowflakes and SJW will do when the Great Storm of 1703 comes around again!”

      Blame it on anthropogenic CO2 emissions of course!

  9. As a British hydrologist familiar with many of the rivers mentioned I found the paper fascinating and and its conclusion almost unarguable. What is particularly interesting in the fact that they detect no trend in severity flooding is that one might have expected many anthropogenic changes; deforestation, increased land drainage, less flood plain storage due to embankment construction, etc. That these were not detected strengthens the argument that climate change has not led to increased flooding.

    • As in most modern countries, Britain now also has millions of water consumers on massive distribution systems which take water from lakes and rivers on a constant basis. In the past these lakes and rivers probably maintained higher levels and provided less capacity to take up heavy rainfall “events”, so perhaps there is a measure of balance from that condition to today’s drained and paved landscape. Just a thought?

      • No. Generally-speaking, what gets consumed goes down the drain or toilet shortly thereafter for treatment and is then discharged to surface waters.

      • Water consumption was not a factor in the case of the rivers studied. For example the Trent River Basin has a population of around 3 million, at 250 l/person/day this would mean an abstraction of less than 10 m3/s. A flood can be more than 1000 m3/s.

    • And lots of houses have been built on a lot of that narurally occurring flood plain.

      Then the inhabitants complain when the flood comes.

      Some house salesmen could sell overcoats to Panama Isthmus inhabitants – unlike some of my compatriots 300 years ago.

  10. If you Google , The flood of 1900, The flood of 1901, The flood of 1902, etc. you will find floods somewhere every year.

    • Which is why you need some proper academic study of these events, as in this paper, to get beyond the anecdotal.

  11. I think the world is long overdue for a book called, ” What Climate Change?”- wherein is detailed the relative similarity of past floods, temperature highs, temperature lows, Arctic and Antarctic ice conditions, storm frequency, etc. If someone decides to take a crack at it, please be sure to point out the similar inaccuracies of weather forecasting in the past to “climate” forecasting today!

    • Well for Arctic sea ice there does not seem to be anything like the current low level for many decades -going back well before the satellite era. This is according to well refernced papers published by experts with a track record of publishing in thiat area, as is the subject of this article. I am in favor of accepting such works as worthy of consideration, if not the final word on any subject. it strikes me as inconistent if you are happy to accept the conclusions of this study (that the frequncy of floods in the UK recetly has been unexceptional), but reject the conclusion of the other, equally well referenced and with equally good credentials, studies (that Arctic sea ice loss is exceptional).

      You see, we can have standards. We can accept peer reviewed papers as a basis for our understanding. Or we can choose to acccept only those papers that confirm our ideas. I could reject this paper as wrong because it suggests that global warming has not increased the frequency of floods in the uk. However, I see no reason to do so based on the paper itself.

      So for the Arctic sea ice, I could accept the conclusions of peer reviewed papers reconstructing Arctic sea ice, or I could reject this science and sieze on one graph showing low levels of sea ice in the early 1970,s, based on poorly understood early satellite data.

      I cannot consistently reject the sea ice papers and accept this flooding paper. Both are based on historical reconstructions.

      So I am happy to say that the evidence that I am aware of points to reducing Arctic sea ice and no measurable increase in frequency of flooding in the UK. This is following the evidence, wherever it takes you.

      If you find that you reject the sea ice papers, whilst accepting this flooding paper, you should seriously ask yourself why and just check for confirmation bias..
      http://www.nature.com/nature/journal/v479/n7374/abs/nature10581.html

      Walsh, J. E., Fetterer, F., Stewart, J. S. and Chapman, W. L. (2016) A database for depicting Arctic sea ice variations back to 1850. Geographical Review, doi:10.1111/j.1931-0846.2016.12195.x

      • And, just why is any additional loss of Arctic sea ice from today’s current extents a matter of concern? Less sea ice (over the entire year) = more heat loss (over the entire year.)

      • RACook. Did I say it should be a matter of concern? Fine if you want to argue that ice is at a level unprecedented in hundreds of years, but we don’t need to worry about it. That is consistent with the science and a matter of values. I am happy with such arguments. Nice to have you on board.

      • RACookPE1978, you are correct, more sea ice loss = more heat loss. However, the loss is not enough to keep up with rising temperatures. If it were enough, the loss of sea ice would stop. Since it is not enough, we lose more sea ice. Please, tell us what happens when all the ice is gone? After it is all gone, the heat loss will reach it’s maximum amount and then what happens?

      • Ice melts in summer, re-freezes in winter. That is how that whole climate thingy works, has for millennia, long before humans showed up. I wonder, what convenient excuse will materialize to explain away the several cancelled Arctic Sea expeditions of this particular season? Since they are being cancelled because of too much ice, that apparently is not supposed to be there. Hmmmm, what could possibly ‘splain all that ice away? Mayhaps all those so very disappointed “climate scientists” could donate some of that money they were going to piss away paddling about the ice filled Arctic Ocean to people who are recovering all this “unprecedented” flooding? Do something useful, for once.

      • …obviously the hydrogen in the water begins to fuse and the entire earth is turned into a blazing sun!

      • It’s warmer now than during the Little Ice Age.
        Stands to reason that there would be less Arctic sea ice.

      • Like most warmunists, seaice really does believe that history started with the satellite era.

      • MarkW. Please read my comment before replying. I was referring to reconstructions that go back further than the satellite era, in much the same way as the subject of this post does with flooding frequency in the UK.

  12. So, a study of the historical record shows that, well, it floods from time to time. Who woulda thunk it!?!? Apparently not “climate scientists” who depend on spreading hysterical nonsense to insure a continued supply of OPM.
    I’ll be sending this pdf link to lots of people, some of whom will be happy to see it.

  13. A recent study in New Hampshire identified similar relationship of recent flooding headlines to historic flooding data — where recent floods may have been more reported, but have not been historic in terms of levels or frequency. This report was in response to a government commission that claimed heightened risks to flooding and SLR for the seacoast area. The analysis of the government report showed no long term trends in SLR, river floods or extreme precipitation over the course of the last 50-100 years.

    The alarmism seems to center around this flooding/SLR events even though the data certainly doesn’t support any events/patterns outside of normal natural variability. The more studies like this which show that weather events today are just as “normal” as they have been over the past century or more, the harder it will be for alarmists to keep up a drum beat that we are heading for tipping points and disaster.

  14. If there is no increase in long term flood frequency (which I understand to be the case globally), why is it that both graphs look like there has been? That is, if I were to estimate a trend line over the first graph, it would have a positive trend. Similarly, the second graph looks “heavier” at the recent end. Are my eyes fooling me? The national flood rich phases (on the very right of the second graph) also show many more of these in the recent period than the earlier.

  15. Flooding seems to be somewhat delightfully and imprecisely defined by most when an area of land that is usually dry is covered with water after heavy rain or after a river or lake flows over its banks.

    Changes to land use – agricultural and housing – logging, confining and narrowing river channels, loss of salt marshes, road and rail infrastructure, mitigation measures (overflow channels, dredging, weirs etc) etc etc all impact on actual flooding.

    More useful would be the incidence of high intensity rain of limited duration over a particular area/catchment. This would provide an understanding of (a) whether the incidence of potential flood events has changed, and the extent to which human activity has made the outcome better or worse.

  16. Essay Somerset Level covers this general UK presumption in some detail. A milleniumm of swamp drainage undone by twenty years of EU mandated drainage neglect. The inevitable floods falsely blamed on climate change. Good paper, but not new news.

  17. I wonder if this study took into account the very many flood defence schemes constructed in the UK in the latter part of the 20th century?

    Or the intensity of the floods?

    Carlisle has seen two 21st century floods at over the ‘1 in 100’ year level within this century… each easily exceeding previous records (1830s before 2005) and in the second event overtopping new flood defences even after local dredging.

    Exeter had a huge flood sceme built (if I recall correctly) after 1968 floods, which kept it safe into this century – since which time there has been more than one flood close road and rail after filling the flood relief channel…

    The intensity of the rainfall in the region has increased, associated with slow moving bands of heavy rain.

    Really, this century has seen severe flood events in every year in the UK except, puzzlingly, 2006…

    this has included summer flash floods/thunderstorms, surface water flooding, ground water flooding and storm surges.

    The places that flood are not new builds on flood plains, but areas close to rivers which have not seen inundation in one, two or three hundred years. And now have flooded more than once.

    The change in climate pattern which has brought this about is well documented.

    (London is drowning and I live by the river…)

    • “The places that flood are not new builds on flood plains, but areas close to rivers which have not seen inundation in one, two or three hundred years. And now have flooded more than once.”

      Really? This is a blatantly biased statement.

      Councils have been giving planning consent for many years on flood plains knowing full well they will flood eventually but they need to build to keep up with demands.

      From the FT
      UK building 10,000 homes a year on floodplains

      https://www.ft.com/content/bfa49cb0-acbf-11e5-b955-1a1d298b6250?mhq5j=e1

      And this plucked from thin air biased statement

      “The change in climate pattern which has brought this about is well documented.”

      Does “well documented” mean proved to be true in your eyes? It certainly does not to me especially when compiled by those looking for an expected outcome.

      As for this statement
      “(London is drowning and I live by the river…)”

      I am happy to buy your property at 1/10 current price because of your perceived risk of inundation which I do not share.

    • Griff, I wondered the same sort of thing. The paper was about frequency rather than intensity. The River Eden section (Carlisle) did say that the two recent floods were significantly larger in terms of water flow than any other historically.

      However the change in land use could presumably work in both directions. Flood relief schemes should reduce flooding frequency, but maybe they are only needed because there is more run-off due to building or land use? It must be a very complicated picture and I guess beyond the scope if this paper.

    • “(London is drowning and I live by the river…)”

      How odd, I did a fair bit of googling and found no reports of flooding other than that caused by equinoctal high tides. In short, there is NO evidence to support the above assertion.

      • “The ice age is coming, the sun is zooming in
        Meltdown expected, the wheat is growin’ thin
        Engines stop running, but I have no fear
        ‘Cause London is drowning, and I, I live by the river”

        The Clash, 1979

        Long before climate change was a twinkle in Hansen’s eye….

    • “(London is drowning and I live by the river…)”

      No it isn’t, not even close.

      Stop making stuff up.

      Have you apologised to Dr. Crockford for lying about her professional qualifications yet?

  18. Ran across pix of floods in the Cincinnati area (Great Miami, Little Miami, Ohio rivers) from 1913 and 1937. Cincinnati & Hamilton County Public Library. (They also have a sweet high-res panorama copper-plate daguerrotype from 1848 Spring at about 12:51, as I recall, based on a couple clock towers included.)

  19. That a lot of UK flooding takes place in well established areas rather than flood plains may simply be:

    – older properties were typically built near to actual water providing transport, sewage, drinking water
    – building on flood plains often includes flood relief measures
    – but the run-off from impermeable surfaces simply increases the short term loading in the watercourse
    – agricultural use changes and road drainage similarly increases run off speed
    – rivers have been narrowed and contained. Previously agricultural land may have flooded harmlessly

  20. friends
    I did do a study on rainfall in the UK
    find it a bit similar to what I find here (in South Africa)

    works a bit like the pendulum of a clock
    [ask me more if you are interested and I must do some work to find the files concerning UK]

  21. Nice paper but the guts of the UK flooding problem are due to …. the EU. Prior to the UK joining the Common Market it was the law that adjacent landowners had the responsibility of draining waterways. When we joined the Common Market this was revoked to fall in line, and as a result responsibility lapsed and dredging didn’t happen.

    This exacerbated what is posted here, that parts of the UK were very much prone to flooding, everyone knows this. Not dredging the waterways just made things a whole lot worse. So the main problem is not Ma Nature, more Ma Merkel and her predecessors.

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